Battery charger



FIG. 1 is a front perspective view of a battery charger;

FIG. 2 is a front elevational view of the battery charger;

FIG. 3 is a back elevational view thereof;

FIG. 4 is a left elevational view thereof;

FIG. 5 is a right elevational view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken line showing of structure is for illustrative purposes only, and forms no part of the claimed design. 

CLAIM The ornamental design for a battery charger, as shown and described in the Figures. 